What’s some of the best Summer food plots for whitetails?

I’m in north Texas, kinda dry & droughthy of course, but decent ground.

Legume. Iron clay/black eyed peas, lab lab, or soybean

The simple route is something like Turner seed spring deer mix or MBS spring deer blend.
Ether can be followed by their fall deer/wildlife blends.

From there ( going away from prepared mixes) it comes down to determining the exact species you’d like, selecting seed varieties & rate and having them custom mixed or mix them yourself.
I know Turner will custom blend anything you want. Very helpful folks that will help you make selections or give recommendations.
They're just S of Breckenridge.

LabLab & various varieties of Cowpea's, Okra, Soybean, Buckwheat, Lespedeza with a little native or maximillian sunflower are good choices.

Where is Turner seed? Looks like I will be helping out with a place in NE Lampasas county but not sure what seed/blend would work best there for planting in the near future???

Just S of Breckenridge, I've used their seeds in many areas of the state.

---> Turner seed <--- click the link.

X2 on the Iron&Clay peas.

Is this a summer plot only? If so then you might look into Sunn Hemp. It has rapid growth and deer love it. A bit drought tolerant. The bad is it is what rope fibers are made from, so you want to not let it get to maturity or you will issues trying to mow it down. It does best if you can shred it when it gets up to about 30"-36" back down to about 16"-18" tall...if it gets to much rain and not enough deer on it. That way you are not dealing with less hemp fiber. I am planting a 3 acre field of Sunn Hemp and Red Ripper cowpeas next week or two. I am hoping the deer hit the peas and let the hemp get started then I have to maintain it to a 18" height if the deer don't.

Purple hull peas and black eyed peas....

X3 on the Iron&Clay peas. They take less water but you still need rain to keep them going. I have had better look planting them in October. Good luck with what ever you choose!